Gun firing mechanism



B. P. JOYCE Jan. 3, 1939.

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GUN FIRING MECHANISM Filed Sept. 19, 1955 8 Sheets-Sheet 6 W wuemtoz Q YA/V P Javar uni? QQ W B P. JOYCE Jan. 3, 1939.

GUN FIRING MECHANISM Filed Sept. 19, 1955 8 Sheets-Sheet 7 m m 5 m m a 2 9 G P M. y mm Q m mm M M e 2 V m% Q 7 h 2 b "I" 1 E %Q\ Q H; Q 3 aaa U. P J I g E %Q \Q\ W aw 2 A Q e I. m e n B. P. JOYCE Jan. 3, 1939.

GUN FIRING MECHANISM Filed Sept. 19, 1935 8 Sheets-Sheet 8 .E r II II Patented Jan. 3, 1939 UNITED STATES PATENT orrics GUN FIRING MECHANISM Application September 19, 1935, Serial No. 41,317

12 Claims.

This application is a continuation in part of my parent U. S. application Serial No. 754,150, filed November 21, 1934.

The invention relates to a gun designed primarily for use upon aircraft and it aims to provide a new and improved firing mechanism allowing either automatic or manual operation of the gun and capable also of preventing firing when desired.

The gun is of a type in which a slidable breech .block is moved to closed position under the infiuence of a spring, and in which the closing of said breech block swings a sear lever to cock a firing pin, and further objects are to provide novel means to prevent any rebound of the breech block under the influence of the firing pin spring after said breech block closes, and to make novel provision whereby the firing mechanism is locked. against action until said breech block is fully closed.

With the foregoing and other objects in view which may become aparent as description proceeds, the invention resides in the novel subject matter hereinafter described and claimed, description being accomplished by reference to the accompanying drawings.

Fig. 1 is a perspective view illustrating the general arrangement of parts and showing the gunner in the gunners basket in readiness for action.

Fig. 2 is a side elevation partly broken away and in section.

Fig. 3 is a vertical longitudinal sectional view partly broken away showing the parts in position for firing, herein referred to as battery position.

Fig. 4 is a front elevation.

Fig. 5 is a fragmentary longitudinal sectional view partly in elevation illustrating primarily parts of the firing and magazine mechanisms and parts of the actuating means for the rotary spider which feeds the rounds from the magazine.

Fig. 6 is a vertical transverse sectional view substantially on line 6-6 of Fig. 5.

Fig. '7 is a vertical sectional view partly in elevation showing the breech block lowered and illustrating the manner in which the empty shell cases ejected from the gun are deflected into a receiver. a

Fig. 8 is a fragmentary side elevation showing part of the actuating mechanism for the firing means.

Fig. 9 is a vertical transverse sectional view on line 99 of Fig. 8.

Fig. 10 is a fragmentary side elevation showing parts of the mechanism for actuating and controlling the firing means, viewed as indicated by the arrow III of Fig. 9.

Fig. 11 is a bottom plan view of a number 0 the parts shown in Fig. 8.

Fig. 12 is a perspective view illustrating the principal parts of the mechanism for actuating and controlling the firing means.

Fig. 13 is a top plan view.

Fig. 14 is a view similar to Fig. 3 but partly in elevation illustrating the relation of parts as counter-recoil terminates.

Fig. 15 is a perspective view showing the mechanism for cooking the firing pin and looking it in cocked position.

Fig. 16 is a view similar to Fig. 15 but showing the firing pin released.

Fig. 17 is an enlarged longitudinal section partly in elevation showing parts of the mechanism which trips the firing mechanism, showing said triping mechanism in the locked position which it occupies from the time the breech block opens until it fully closes.

Fig. 18 is a view similar to Fig. 1'7 but showing the tripping mechanism for the firing mechanism released in readiness to permit firing.

Fig. 19 is a view similar to Figs. 17 and 18 but showing the relation of parts when firing is effected.

Figs. 20 and 21 are transverse sectional views on lines 20-20 of Fig. 19 and 2|--2| of Fig. 17, respectively.

Fig. 22 is a top plan view of the piston which forms part of the breech block closing means and carries a cam for actuating the locking means of the mechanism which trips the firing mechanism.

Figs. 23 and 24 are side elevations of the locking rod for the aforesaid tripping mechanism.

The specific construction shown in the drawings will be definitely described with the understanding, however, that within the scope of the invention as claimed, numerous variations may be made, the disclosure being illustrative rather than limiting.

I have shown an annular track 50 (Fig. 2) to be secured to an aircraft (not shown) around the edge of a cockpit. Partly overlying and partly within and concentric with the track 50, is a ring 5| from which pipes or other structural members 52 project downwardly, the lower ends of said members 52 being connected by other pipes or structural members 53 so that the ring 5| and the various structural members 52, 53 cooperate in forming a gunner's basket in which an adjustable seat 54 may be provided for the gunner.

Two gun-mounting side frames 59 span, the ring 5| and are secured thereto, and the gun is supported on these side frames by trunnions 60 so that said gun may be elevated or depressed as required. A hand wheel 6| is provided to effect turning of the gun about the trunnions 60. The hand-wheel BI is operated by the gunner's left hand, and rigid hand grips 61 are shown projecting outwardly from the track 50 to be engaged by his right hand, so that by pushing or pulling on these hand grips, the gunner may rotate the entire basket and the gun to traverse the latter, said hand grips 61 being shown only in Fig. 1.

A brake 68 (Fig. 13) is carried by the basket to engage the track 50, and a cable I6 depends from said brake to a brake pedal 11 (Figs. 1 and 13) mounted in the lower end of the gunners basket in position to be engaged by his right foot. A supporting plate 18 may be provided for the left foot as shown in Figs. 1 and 13, but when the gun is being operated, this foot engages a firing pedal I9 which is mounted in the gunners basket and is connected with the lower end of a cable 80, the upper end of this cable being connected with a mechanism hereinafter described for effecting either single shot operation of the gun or automatic operation.

The gun is of a type to receive the rounds shown at 82 in a number of the views, from a clip 83 within a magazine 84. The rounds 82 fed from the magazine 84 are automatically loaded into the gun by a loading tray I60 and a loading plunger I6I, and upon counter-recoil, the empty shell cases 85 are rearwardly ejected into a receiver 86.

The trunnions 60 above described support a cradle shown at I04 in a number of the main views, and the gun barrel I05 is slidably mounted in said cradle in any preferred way so that it may recoil and counter-recoil. A recoil check is shown at I06 and a counter-recoil spring at I01, and appropriate counter-poise mechanism is illustrated in a general way at I08.

The gun barrel I05 is provided with a vertically slidable breech block I09 carrying a conventional firing pin H and its spring H0 and a bell crank or sear lever III connected with said pin. Suitable ejectors II2 are provided to eject the shell cases 85 when the breech block I09 lowers upon counter-recoil of the barrel I05, said ejectors serving also to hold said breech block in lowered position until the next round is loaded into the gun breech. For operating the ejectors H2 and for causing them to temporarily lock the breech block I09 lowered, studs II3 are provided on the ejectors mounted in slots H4 in the breech portion of the gun and operable in grooves H5 in the sides of the breech block (see Fig. 7) I have not gone into any particular detail with regard to these structural features, for they are known.

The rear portion of the gun barrel carries a transverse rock shaft II6 having an arm II'I connected with the breech block I09, for lowering and raising said breech block, one end of said shaft II6 being preferably squared as seen in Fig. 5 to be engaged by a hand crank or the like, if desired. The other end of shaft H6 is provided with an operating arm II8 (Figs. 5 and 6) which is cooperable with a known oneway dog II9 (Figs. 5 and 6) to lower the breech block I09 after recoil has occurred and counterrecoil has started. Upon recoil of the gun barrel, the arm I I8 merely swings the dog I I9 out of its way as shown in dotted lines in Fig. 5 but upon counter-recoil, dog II9 operates arm II8 to turn shaft I I6 and lower the breech block. When this occurs, the ejectors II2 eject the empty shell case 85 and then serve to hold the breech block lowered until a new round is inserted.

Suitably connected with the shaft H6 is the chain of an assemblage of chain I20, piston I2I,

and spring I22. When the breech block I09 lowers, the chain I20 is pulled, causing movement of the piston I2I to compress the spring I22. As soon as the breech block is released by insertion of a round into the gun barrel, spring I22 expands and moves piston I2I and chain I20 to again raise the breech block. During this raising, the sear lever III coacts with a nose I23 on a trigger shaft I24 to retract the firing pin IIO against the action of spring 0* as shown in Fig. 3, said firing pin and sear lever being held cooked by a spring pressed latch pin II0 mounted in the breech block I09 to prevent said spring from causing rebound of said breech block when the latter reaches closed position. If the gun be set for manual control as hereinafter described, the firing pin II 0 will remain retracted until the gunner depresses the firing pedal I9 but if the gun be set for automatic operation, said firing pin will be released as soon as the breech block I09 is entirely closed. The trigger shaft I24 is provided with a releasing cam II0 for latch pin H0", and is provided on one end with a firing trigger I25 which is in the rearward path of an arm I26 (Fig. 5), said arm I26 being loosely pivoted at I21 to the left side of the breech portion of the gun barrel. The rear end of a longitudinally extending rod I28 abuts the arm I26 (see Figs. 5, 9, and 12),

said rod I28 extending forwardly through a suitable guiding casing I29 and being provided with a spring I30, said spring being operable to rearwardly force said rod I28 to effect firing of the gun, after said rod is forwardly forced to compress spring I30 and then released.

The lower end of arm I26 is bifurcated and straddles a rotatable and slidable locking rod I26 which is mounted in bearings I26 and I26 at the front and rear ends of the cylinder I2 I which guides the piston I2 I, said rod I26 being disposed over said cylinder. This rod I 26 is provided with a collar I26 to abut the rear edge of the arm I26 for swinging said arm I26 forwardly to forwardly slide rod I28 and compress spring I30 when said rod I26 is forwardly slid, and this forward sliding of rod I26 is effected by a lug I26 on piston I2I when this piston is pulled forwardly upon lowering of the breech block I09, during counter-recoil. Whencounter-recoil has almost been completed, arm I26 contacts with rod I28 forcing it forwardly and compressing spring I30. If,- the gun be set for manual operation, the rod I28 will remain in its forward position due to the latching means hereinafter described, but if the gun be set for automatic operation, just as soon as the breech block closes, spring I 30' actuates the rod I28, causing the arm I26 and trigger arm I25 to turn trigger shaft I24, releasing thesear lever latch pin II0 and the sear lever III to release the firing pin IIO.

Until the breech block fully closes, the rod I26 locks the arm I26 against rearward movement, due to construction now to be described (see more particularly Figs. 17 to 21), and therefore, the gun cannot be prematurely fired. The front end of rod I26 is provided with two longitudinal ribs I26 slidable in grooves I26 in the bearing I26 and when said rod I26 reaches its foremost position, said ribs I26 are clear of said grooves I26 A cam I26 on the piston lug I26 then turns a cam I26 on collar I26 and turns rod I26 to dispose the ribs I26 out of alinement with the grooves I26 These ribs and the bearing I26 then prevent rod I26 from sliding rearwardly,

and the gun cannot, therefore, fire until said ribs are released from said bearing. This is accomplished when the breech block I09 closes, by means of a second cam I26 on the piston lug I26 and a cam I26 on the rod I26. As piston I2I completes its breech-block-closing movement, its cam l'iIi engages cam I265 and turns rod I26 until the ribs I26 are in alinement with the grooves I26 The rod I26 is then free to slide rearwardly and the gun can consequently be fired by rod I28 swinging arm I26 against the firing trigger I25.

A latch I34 (Figs. 2, 9, l0 and 12) is provided for coaction with the rod I28 to hold the latter against movement under the influence of the spring I30 after said rod has been forwardly moved to compress said spring. but this latch I34 is permitted to function only if the gun is being manually instead of automatically fired. If manual firing is to be effected, the latch I34 is allowed to hold the rod I28 in the forward position shown in Figs. 10 and 12, until firing is to be accomplished. Then. the release of latch I34 will allow rod I28 to move rearwardly under the infiuence of the spring I30, tripping the firing mechanism as above explained. If the gun is being automatically operated, the latch I34 is held in released position so that after each forward movement and release of rod I28, spring I30 will rearwardly slide said rod as soon as the breech block closes.

In the present showing, the latch I34 is in the form of an inverted L pivotally mounted at I35 upon the portion I36 of the cradle which contains the counter-recoil spring I01, and the horizontal arm of said latch is cooperable with a downwardly projecting stud I31 on the front end of rod I28. The vertical arm of the latch I34 is pivotally connected at I38 with a shaft I39 (Figs. 8, 9, 10 and 12), said shaft passing rotatably through a portion of the cradle and being also slidable. Pulling the shaft I39 in one direction releases the latch I34 and compresses a spring I40 which surrounds said shaft. A slidable member I 4| connected with the cable above described, is provided for pulling the shaft I39 in latch-releasing direction and then releasing said shaft if manual firing is to be effected, or for pulling said shaft to latchreleasing position and holding it in this position if automatic firing is to be carried out. The member MI is shown more particularly in Figs. 8, l1 and 12 and this member is cooperabe with a short lug I42 or a long lug I43 on the shaft I39. The member MI is provided with one cam portion I44 for coaction with the lug I42 when manual firing is to be effected, and is provided with another cam portion I45 for coaction with the long lug I43 when the gun is to fire automatically. and the shaft I 39 may be turned by means of a crank I46 to dispose either of said lugs in operative relation with the member I4I or to so locate said lugs that neither one of them can be engaged by said member I4I. A latch pin I41 is slidable in the handle of the crank I46 and is releasable by a knob I48, said latch pin being cooperable with three sockets I49 in the adjacent portion of the gun cradle (Fig.-

10). The latch pin may thus be used for holding the shaft I39 in any one of its three positions.v

When said shaft isset as shown in Figs. 8 and 9, each time the member MI is pulled by the cable 80, the cam portion I44 engages the short lu I42, pulling the shaft I39 to release the latch I34, allowing firing of the gun, and just as soon as the latch has been released, said cam portion I44 releases the lug I42 and spring I40 returns said shaft I39, so that latch I34 is in readiness to again hold rod I28 when this rod is again forced forwardly. For manual firing, the operator of course releases the foot pedal I9 after the shot has been fired. whereupon a spring device I50 returns the member I4I to its normal position.

When the shaft I39 is turned to place the long lug I 43 in operative relation with the cam portion I45 of the member I4l, the gunner will depress the foot pedal I9 and hold it depressed. This causes the cam portion I45 of member I to engage lug I43, slide shaft I 39 to release latch I34 and hold this latch in released position so that rod I28 may rearwardly return each time it is forced forwardly, thus effecting,automatic-firing. When shaft I39 is set in a neutral position, operation of member I4I cannot effect movement of said shaft.

The member I is preferably of the L-shape shown in Fig. 11, being bifurcated to straddle a fixed track I5I which issuitably secured to the gun cradle, said track I5I having a longitudinal slot I52 which receives a pin I53 carried by the member I4I. This member I 4| is thus effectively guided and is allowed a tilting movement as shown in dotted lines in Fig. 11. This tilting movement is necessary in order to allow member I4I to pass the end of shaft I39 carrying the lugs I42 and I43 as member I4I is returned to its normal position by the spring device I50, said member I4I then clicking idly over said lug I42.

A pivotally supported lock I54 is shown, capable of positively locking the rod I28 in guncocked position, said lock being suspended from a shaft I56 controlled by a feeler I59 in the magazine 84 to prevent firing of the last round in the gun before placing a new clip of rounds in said magazine. If the last round from the magazine were fired after insertion into the barrel breech. further automatic operation could not be effected upon insertion of a new clip, without first loading the gun by hand. Such hand loading, however, is not required by leaving one unfired round in the gun, as above described.

When the gun has been automatically operating and the last round is loaded into it, the gunner of course releases the foot pedal I9 before inserting a new clip of rounds into the magazine 84. This insures that by the timethe lock I54 is released, latch I34 will be in position to hold the rod I28 against movement in gun-firing direction. Otherwise, the rod I28 would effect gun firing immediately upon insertion of a new clip and consequent release of lock I54.

While the operation of the structure as a whole would probably be understood from explanations hereinbefore given in connection with the various groups of coacting elements, it may be briefly explained as follows'z-The initial round is, of course, inserted by hand by manually lowering the breech block I09 with a crank or the like applied to the squared end of the shaft II6. Lowering the breech block pulls upon chain I20, compressing spring I22 and moving piston I2I (see Fig. 5) forwardly. During the forward movement of piston I2I, itscam I26 pushes against the cam I26 of rod I26, this rod being now held against rotation by the ribs I26 in the grooves I 26 so that said rod is slid forwardly, causing its collar I26 to forwardly swing the arm I26, forwardly sliding the rod I28 and compressing the spring I30, so that the entire tripping means for the firing means (I25, I 24, I23, III, I I0, H0) is set in readiness for action. As soon as thisis accomplished, the ribs I26 clear the grooves I26 and the rod I26 is turned under the influence of the cams I26 and I26 to dispose said ribs I26 out of alinement with said grooves, prohibiting the rearward movement of said rod I2Ii and arm I26 necessary to trip the trigger arm I25 and fire the round, until the rod I26 is released. This release is effected only when the breech block I09 closes as will be more fully explained. We will now assume that the crank I46 (Figs. 10 and 12) has been moved upwardly and forwardly to theone shotposition so that the latch I34 will engage the rod I28in its forwardgun-cockedposition. After inserting the first round by hand, the breech block is allowed to close under the influence of the spring I22 and as said breech block closes, the sear lever III and finger I23 coact to retract'the firing pin I I0, and the latch pin II0 engages said sear lever to hold it retracted as seen in Figs. 3 and 15. The rearward movement of piston I2I incident to breech-block-closing, causes the cams I26 and I26 to turn rod I26 to realine the ribs I26 with the grooves I 26 said cams then pushing said rod I26 rearwardly to move collar I26 away from arm I26, so that this arm may be rearwardly swung by rod I28 when latch I34 is released. Depression of the firing pedal I9 will now pull cable 80 and actuate the member II to pull the shaft I39 in a direction to release the latch I34, allowing rod I28 to slide rearwardly under the influence of spring I30, rocking shaft I24 to release the latch pin IIll' and trip the firing pin IIO to fire the round. It is to be recalled that at this time, the lock I54 is held in released position by one of the rounds in the magazine contacting with the feeler I59, so that said lock will not interfere with rearward sliding of the rod I28. As soon as the round is fired, recoil of the barrel occurs, and then counter-recoil, these movements serving to actuate the shell-ejecting and barrel-reloading mechanism.

If the crank I46 be set for automatic operation, the gunner depresses the firing pedal 19 and holds it depressed so that the member I4I will hold the shaft I39 and in turn hold the latch I34 in released position. With this latch so held, it cannot hold the rod I28 the next time the latter is forced forwardly by arm I26. Consequently, just as soon as the breech block is closed after the automatic loading of the round into the breech, the rod I28 will he slid rearwardly by the spring I30 causing arm I26 to strike the firing trigger I25, releasing the firing pin H0 and firing the round. The gun will now operate automatically as long as the firing pedal I9 is held depressed until the last round from the magazine 84 has been loaded into the breech. When this has occurred, however, the lock I54 automatically prevents firing of this last round until the magazine is reloaded.

Whenever desired, the crank I46 may be set in its neutral or safe position so that any movement which may be imparted to the member MI by the firing pedal I9, will not cause firing of the gun.

Attention is again invited to the possibility of making numerous variations within the scope of the invention as claimed.

I claim:-

1. In an automatic gun having an automatically actuated breech block, and automatically cocked firing means having a firing trigger; tripping means for said firing trigger self-actuated when forced in one direction and released, and

means operatively connected with said breech block and said tripping means for forcing the latter in said one direction when said breech block is opened and for releasing said tripping means when said breech block is closed.

2. In an automatic gun having a breech block, automatic actuating means for said breech block including an assemblage of spring, pull chain and piston for closing said breech block, the chain and piston being movable by opening of the breech block to store energy in said spring, and automatically cocked firing means having a firing trigger; tripping means for said firing trigger self-actuating when shifted in one direction and released, said piston and said tripping means having coacting portions for shifting said tripping means in said one direction when the breech block is opened and for releasing said tripping means when said breech block is closed.

3. .In an automatic gun having an automatically actuated breech block, and automatically cocked firing means having a firing trigger; tripping means for said firing trigger self-actuating when forced in one direction and then released, means operatively connected with said breech block and said tripping means for forcing the latter in said one direction each time said breech block is opened and for freeing said tripping means each time said breech block is closed, latch means for latching said tripping means when moved in said one direction if the gun is to be held in cocked position, manually operable releasing means for said latch means embodying means adjustable to one position at which said releasing means will release said latch and then allow return of the latter to operative position, to a second position at which said releasing means will hold said latch means in released position for automatic gun operation, and to a third position at which said releasing means cannot release said latch means.

4. In an automatic gun having a member which is forced in one direction and is then self-shifting in the other direction to effect gun firing; a latch engageable with said member to hold the gun in cocked position, a self-returning rod connected with said latch for releasing it, means mounting said rod for rotation and sliding, a relatively short lateral lug and a relatively long lateral lug on said rod, a movably mounted mannally operable member for moving said rod in latch-releasing direction, said member having a cam portion for coaction with said short lug to move said rod and then release it, and having another cam portion cooperable with said long lug for moving said rod to released position and holding it in said released position, and means for rotating said rod to one position at which said short lug and its respective cam portion will coact, to a second position at which said long lug and its respective cam will coact, and to a third position at which neither lug will be engaged by either cam portion.

5. In an automatic gun having a breech block, automatic actuating means for said breech block including an assemblage of spring, pull chain and piston for closing said breech block, the chain and piston being movable by opening of the breech block to store energy in said spring, and automatically cocked firing means having a firing trigger; tripping means for said firing trigger cooperatively related with said piston and shiftable to a set position by movement of said piston in breech-block-opening-direction, and means cooperatively related with said piston and releasable by movement of said piston to breechblock-closing-position for holding said tripping means in said set position until the breech block closes.

6. In an automatic gun having a breech block, automatic actuating means for said breech block including an assemblage of spring, pull chain and piston for closing said breech block, the chain and piston being movable by opening of the breech block to store energy in said spring, and automatically cocked firing means having a firing trigger; tripping means for said firin trigger cooperatively related with said piston and shiftable to a set position by movement of said piston in breech-block-opening-direction, and means cooperatively related with said piston, applied by the movement of said piston in said breech-block-opening-direction and released by movement of said piston to breech-block-closingposition for holding said tripping means in said set position until the breech block closes.

I. In an automatic gun having a breech block, automatic actuating means for said breech block including an assemblage of spring, pull chain and piston for closing said breech block, the chain and piston being movable by opening of the breech block to store energy in said spring, and automatically cocked firing means; tripping means for said firing means including a member movable substantially uni-directionally with said piston, a slidable and rotatable rod mounted parallel with the line of travel of said piston, said rod having a shoulder positioned to abut said member and move it to a set position in readiness for action, coacting means on said piston and rod for sliding said rod to a predetermined position when said piston moves in breech-blockopening-direction to set said member and for then turning said rod, means applied by said turning of said rod for holding the rod in said predetermined position, and coacting means on said piston and rod for reversely turning said rod to release said holding means therefor when said piston moves to breech-block-closingposition.

8. In an automatic gun having a breech block, automatic actuating means for said breech block including an assemblage of spring, pull chain and piston for closing said breech block, the chain and piston being movable by opening of the breech block to store energy in said spring, and automatically cocked firing means; tripping means for said firing means including a member movable substantially uni-directionally with said piston, a slidable and rotatable rod mounted parallel with the line of travel of said piston, said rod having a shoulder positioned to abut said member and move it to a set position in readiness for action, a bearing in which said 'rod is slidable and rotatable, said bearing being provided with a groove and said rod with a rib which slides in said groove until said rod reaches a position at which said member is in said set position in readiness for action, said rib then clearing said groove, coacting means on said piston and rod for sliding the rod to said position as said piston moves in breech-block-opening-direction and for then turning said rod to cause said rib to abut said bearing and temporarily hold said rod and said member against return, and coacting means on said piston and said rod for reversely turning the latter to again aline said rib with said groove as said piston reaches breech-block-closed-position.

9. In a gun having a breech block carried by the breech portion of the gun barrel, opening and closing means for said breech block, a springactuated firing pin mounted in said breech block, a sear lever fulcrumed in said breech block and so connected with said firing pin that the latter may be cocked by swinging said sear lever, anda trigger shaft mounted on said breech portion of the gun barrel independently of the breech block and having a trigger portion to abut said sear lever and swing the same to cock said firing pin as the breech block closes; a self-applied latch mounted in said breech block in position to engage said sear lever and hold it in firing pin-cockedposition, and means actuated by said trigger shaft for releasing said latch when said trigger shaft is turned to release said trigger portion from said sear lever.

10. In a gun having a breech block carried by the breech portion of the gun barrel, opening and closing means for said breech block, a springactuated firing pin mounted in said breech block, a sear lever fulcrumed in said breech block and so connected with said firing pin that the latter may be cooked by swinging said sear lever, and a trigger shaft mounted on said breech portion of the gun barrel independently of the breech block and having a trigger portion to abut said sear lever and swing the same to cock said firing pin as the breech block closes; a self-applied latch mounted in said breech block in position to engage said sear lever and hold it in firing-pincocked-position, and a cam on said trigger shaft engaging a portion of said latch for releasing said latch when said trigger shaft is turned to release said trigger portion from said sear lever.

11. In an automatic gun, a barrel, an automatically actuated breech block therefor, automatically cocked firing means having a firing trigger mounted on said barrel independently of said breech block, tripping means for said firing trigger mounted on said barrel and including an actuating spring, said trigger tripping means being effective to stress said actuating spring for operation when said trigger tripping means is moved in a predetermined manner, and operating connections between said breech block and said trigger tripping means for moving the latter in said predetermined manner as the breech block opens and for releasing said trigger tripping means upon breech block closing, allowing the stressed spring to actuate said trigger tripping means to fire the gun.

12. In an automatic gun, a barrel, an automatically actuated breech block therefor, automatically cocked firing means having a firing trigger mounted on said barrel independently of said breech block, tripping means for said firing trigger mounted on said barrel and including a longitudinally extending slidable rod and an actuating spring surrounding said rod, said rod being effective to stress said actuating spring for operation when said rod is slid forwardly, and operating connections between said breech block and said trigger tripping means for so movin the latter as to forwardly slide said rod as the breech block opens and for releasing said trigger tripping means upon breech block closing, allowing the stressed spring to actuate said trigger tripping means to fire the gun.

BRYAN P. JOYCE. 

